For the case of violin piano ensemble, we empirically observe sometimes the activity of the violin part would be too sparse, making the two sounds unbalanced in the mixture. We consider it worth investigating whether this would influence the performance of the resulting separation model. Therefore, we apply librosa.effects.split [1]} with
`top db’ \(=\)  20 to remove the silence part in the training/validation data, before dividing them into 10-second chunks for mixing.
We have also experimented with other values of `top db’ and found 20 works better.
